In reducing the power consumption of a logical volume created by using a plurality of storage devices such as disks, the capacities and maximum power consumptions of the respective disks needs to be considered. To be specific, from among configurations capable of building a required capacity, a combination which realizes the minimum power consumption is selected. Moreover, as described in Patent Document 1, from among configurations having a certain performance, a configuration which realizes the minimum power consumption is selected.    Patent Document 1: Japanese Unexamined Patent Application Publication No. JP-A 2013-206101
In recent years, a logical volume is often created by using a plurality of SSDs. Meanwhile, the IOPS performances and power consumptions of SSDs vary depending on venders and capacities. Therefore, simply selecting an SSD with the minimum power consumption may not be enough to obtain a configuration which realizes the minimum power consumption in consideration of an I/O load characteristic.
In other words, regarding a logical volume created by using SSDs, there arises a problem that an appropriate configuration which realizes the minimum power consumption in consideration of a characteristic at the time of use cannot be determined. This may also arise not only when using SSDs but also when determining a configuration of a logical volume created by using other storage devices such as HDDs.